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-rw-r--r--kernel/cgroup.c99
-rw-r--r--kernel/cgroup_freezer.c23
-rw-r--r--kernel/cgroup_pids.c77
-rw-r--r--kernel/cpuset.c33
-rw-r--r--kernel/events/callchain.c2
-rw-r--r--kernel/events/core.c90
-rw-r--r--kernel/events/ring_buffer.c2
-rw-r--r--kernel/events/uprobes.c2
-rw-r--r--kernel/fork.c9
-rw-r--r--kernel/irq_work.c2
-rw-r--r--kernel/jump_label.c2
-rw-r--r--kernel/locking/lockdep.c2
-rw-r--r--kernel/locking/lockdep_proc.c2
-rw-r--r--kernel/locking/osq_lock.c8
-rw-r--r--kernel/sched/clock.c2
-rw-r--r--kernel/sched/core.c48
-rw-r--r--kernel/sched/cputime.c3
-rw-r--r--kernel/sched/fair.c2
-rw-r--r--kernel/sched/rt.c2
-rw-r--r--kernel/sched/sched.h3
-rw-r--r--kernel/sched/wait.c28
-rw-r--r--kernel/stop_machine.c4
-rw-r--r--kernel/trace/trace_event_perf.c2
23 files changed, 270 insertions, 177 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 4466273f59e1..fe95970b1f79 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -98,6 +98,12 @@ static DEFINE_SPINLOCK(css_set_lock);
static DEFINE_SPINLOCK(cgroup_idr_lock);
/*
+ * Protects cgroup_file->kn for !self csses. It synchronizes notifications
+ * against file removal/re-creation across css hiding.
+ */
+static DEFINE_SPINLOCK(cgroup_file_kn_lock);
+
+/*
* Protects cgroup_subsys->release_agent_path. Modifying it also requires
* cgroup_mutex. Reading requires either cgroup_mutex or this spinlock.
*/
@@ -730,9 +736,11 @@ static void put_css_set_locked(struct css_set *cset)
if (!atomic_dec_and_test(&cset->refcount))
return;
- /* This css_set is dead. unlink it and release cgroup refcounts */
- for_each_subsys(ss, ssid)
+ /* This css_set is dead. unlink it and release cgroup and css refs */
+ for_each_subsys(ss, ssid) {
list_del(&cset->e_cset_node[ssid]);
+ css_put(cset->subsys[ssid]);
+ }
hash_del(&cset->hlist);
css_set_count--;
@@ -1032,9 +1040,13 @@ static struct css_set *find_css_set(struct css_set *old_cset,
key = css_set_hash(cset->subsys);
hash_add(css_set_table, &cset->hlist, key);
- for_each_subsys(ss, ssid)
+ for_each_subsys(ss, ssid) {
+ struct cgroup_subsys_state *css = cset->subsys[ssid];
+
list_add_tail(&cset->e_cset_node[ssid],
- &cset->subsys[ssid]->cgroup->e_csets[ssid]);
+ &css->cgroup->e_csets[ssid]);
+ css_get(css);
+ }
spin_unlock_bh(&css_set_lock);
@@ -1369,6 +1381,16 @@ static void cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft)
char name[CGROUP_FILE_NAME_MAX];
lockdep_assert_held(&cgroup_mutex);
+
+ if (cft->file_offset) {
+ struct cgroup_subsys_state *css = cgroup_css(cgrp, cft->ss);
+ struct cgroup_file *cfile = (void *)css + cft->file_offset;
+
+ spin_lock_irq(&cgroup_file_kn_lock);
+ cfile->kn = NULL;
+ spin_unlock_irq(&cgroup_file_kn_lock);
+ }
+
kernfs_remove_by_name(cgrp->kn, cgroup_file_name(cgrp, cft, name));
}
@@ -1832,7 +1854,6 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp)
INIT_LIST_HEAD(&cgrp->self.sibling);
INIT_LIST_HEAD(&cgrp->self.children);
- INIT_LIST_HEAD(&cgrp->self.files);
INIT_LIST_HEAD(&cgrp->cset_links);
INIT_LIST_HEAD(&cgrp->pidlists);
mutex_init(&cgrp->pidlist_mutex);
@@ -2193,6 +2214,9 @@ struct cgroup_taskset {
struct list_head src_csets;
struct list_head dst_csets;
+ /* the subsys currently being processed */
+ int ssid;
+
/*
* Fields for cgroup_taskset_*() iteration.
*
@@ -2255,25 +2279,29 @@ static void cgroup_taskset_add(struct task_struct *task,
/**
* cgroup_taskset_first - reset taskset and return the first task
* @tset: taskset of interest
+ * @dst_cssp: output variable for the destination css
*
* @tset iteration is initialized and the first task is returned.
*/
-struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset)
+struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset,
+ struct cgroup_subsys_state **dst_cssp)
{
tset->cur_cset = list_first_entry(tset->csets, struct css_set, mg_node);
tset->cur_task = NULL;
- return cgroup_taskset_next(tset);
+ return cgroup_taskset_next(tset, dst_cssp);
}
/**
* cgroup_taskset_next - iterate to the next task in taskset
* @tset: taskset of interest
+ * @dst_cssp: output variable for the destination css
*
* Return the next task in @tset. Iteration must have been initialized
* with cgroup_taskset_first().
*/
-struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset)
+struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset,
+ struct cgroup_subsys_state **dst_cssp)
{
struct css_set *cset = tset->cur_cset;
struct task_struct *task = tset->cur_task;
@@ -2288,6 +2316,18 @@ struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset)
if (&task->cg_list != &cset->mg_tasks) {
tset->cur_cset = cset;
tset->cur_task = task;
+
+ /*
+ * This function may be called both before and
+ * after cgroup_taskset_migrate(). The two cases
+ * can be distinguished by looking at whether @cset
+ * has its ->mg_dst_cset set.
+ */
+ if (cset->mg_dst_cset)
+ *dst_cssp = cset->mg_dst_cset->subsys[tset->ssid];
+ else
+ *dst_cssp = cset->subsys[tset->ssid];
+
return task;
}
@@ -2323,7 +2363,8 @@ static int cgroup_taskset_migrate(struct cgroup_taskset *tset,
/* check that we can legitimately attach to the cgroup */
for_each_e_css(css, i, dst_cgrp) {
if (css->ss->can_attach) {
- ret = css->ss->can_attach(css, tset);
+ tset->ssid = i;
+ ret = css->ss->can_attach(tset);
if (ret) {
failed_css = css;
goto out_cancel_attach;
@@ -2356,9 +2397,12 @@ static int cgroup_taskset_migrate(struct cgroup_taskset *tset,
*/
tset->csets = &tset->dst_csets;
- for_each_e_css(css, i, dst_cgrp)
- if (css->ss->attach)
- css->ss->attach(css, tset);
+ for_each_e_css(css, i, dst_cgrp) {
+ if (css->ss->attach) {
+ tset->ssid = i;
+ css->ss->attach(tset);
+ }
+ }
ret = 0;
goto out_release_tset;
@@ -2367,8 +2411,10 @@ out_cancel_attach:
for_each_e_css(css, i, dst_cgrp) {
if (css == failed_css)
break;
- if (css->ss->cancel_attach)
- css->ss->cancel_attach(css, tset);
+ if (css->ss->cancel_attach) {
+ tset->ssid = i;
+ css->ss->cancel_attach(tset);
+ }
}
out_release_tset:
spin_lock_bh(&css_set_lock);
@@ -3290,9 +3336,9 @@ static int cgroup_add_file(struct cgroup_subsys_state *css, struct cgroup *cgrp,
if (cft->file_offset) {
struct cgroup_file *cfile = (void *)css + cft->file_offset;
- kernfs_get(kn);
+ spin_lock_irq(&cgroup_file_kn_lock);
cfile->kn = kn;
- list_add(&cfile->node, &css->files);
+ spin_unlock_irq(&cgroup_file_kn_lock);
}
return 0;
@@ -3530,6 +3576,22 @@ int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
}
/**
+ * cgroup_file_notify - generate a file modified event for a cgroup_file
+ * @cfile: target cgroup_file
+ *
+ * @cfile must have been obtained by setting cftype->file_offset.
+ */
+void cgroup_file_notify(struct cgroup_file *cfile)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&cgroup_file_kn_lock, flags);
+ if (cfile->kn)
+ kernfs_notify(cfile->kn);
+ spin_unlock_irqrestore(&cgroup_file_kn_lock, flags);
+}
+
+/**
* cgroup_task_count - count the number of tasks in a cgroup.
* @cgrp: the cgroup in question
*
@@ -4590,13 +4652,9 @@ static void css_free_work_fn(struct work_struct *work)
container_of(work, struct cgroup_subsys_state, destroy_work);
struct cgroup_subsys *ss = css->ss;
struct cgroup *cgrp = css->cgroup;
- struct cgroup_file *cfile;
percpu_ref_exit(&css->refcnt);
- list_for_each_entry(cfile, &css->files, node)
- kernfs_put(cfile->kn);
-
if (ss) {
/* css free path */
int id = css->id;
@@ -4701,7 +4759,6 @@ static void init_and_link_css(struct cgroup_subsys_state *css,
css->ss = ss;
INIT_LIST_HEAD(&css->sibling);
INIT_LIST_HEAD(&css->children);
- INIT_LIST_HEAD(&css->files);
css->serial_nr = css_serial_nr_next++;
if (cgroup_parent(cgrp)) {
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
index f1b30ad5dc6d..2d3df82c54f2 100644
--- a/kernel/cgroup_freezer.c
+++ b/kernel/cgroup_freezer.c
@@ -155,12 +155,10 @@ static void freezer_css_free(struct cgroup_subsys_state *css)
* @freezer->lock. freezer_attach() makes the new tasks conform to the
* current state and all following state changes can see the new tasks.
*/
-static void freezer_attach(struct cgroup_subsys_state *new_css,
- struct cgroup_taskset *tset)
+static void freezer_attach(struct cgroup_taskset *tset)
{
- struct freezer *freezer = css_freezer(new_css);
struct task_struct *task;
- bool clear_frozen = false;
+ struct cgroup_subsys_state *new_css;
mutex_lock(&freezer_mutex);
@@ -174,22 +172,21 @@ static void freezer_attach(struct cgroup_subsys_state *new_css,
* current state before executing the following - !frozen tasks may
* be visible in a FROZEN cgroup and frozen tasks in a THAWED one.
*/
- cgroup_taskset_for_each(task, tset) {
+ cgroup_taskset_for_each(task, new_css, tset) {
+ struct freezer *freezer = css_freezer(new_css);
+
if (!(freezer->state & CGROUP_FREEZING)) {
__thaw_task(task);
} else {
freeze_task(task);
- freezer->state &= ~CGROUP_FROZEN;
- clear_frozen = true;
+ /* clear FROZEN and propagate upwards */
+ while (freezer && (freezer->state & CGROUP_FROZEN)) {
+ freezer->state &= ~CGROUP_FROZEN;
+ freezer = parent_freezer(freezer);
+ }
}
}
- /* propagate FROZEN clearing upwards */
- while (clear_frozen && (freezer = parent_freezer(freezer))) {
- freezer->state &= ~CGROUP_FROZEN;
- clear_frozen = freezer->state & CGROUP_FREEZING;
- }
-
mutex_unlock(&freezer_mutex);
}
diff --git a/kernel/cgroup_pids.c b/kernel/cgroup_pids.c
index cdd8df4e991c..b50d5a167fda 100644
--- a/kernel/cgroup_pids.c
+++ b/kernel/cgroup_pids.c
@@ -106,7 +106,7 @@ static void pids_uncharge(struct pids_cgroup *pids, int num)
{
struct pids_cgroup *p;
- for (p = pids; p; p = parent_pids(p))
+ for (p = pids; parent_pids(p); p = parent_pids(p))
pids_cancel(p, num);
}
@@ -123,7 +123,7 @@ static void pids_charge(struct pids_cgroup *pids, int num)
{
struct pids_cgroup *p;
- for (p = pids; p; p = parent_pids(p))
+ for (p = pids; parent_pids(p); p = parent_pids(p))
atomic64_add(num, &p->counter);
}
@@ -140,7 +140,7 @@ static int pids_try_charge(struct pids_cgroup *pids, int num)
{
struct pids_cgroup *p, *q;
- for (p = pids; p; p = parent_pids(p)) {
+ for (p = pids; parent_pids(p); p = parent_pids(p)) {
int64_t new = atomic64_add_return(num, &p->counter);
/*
@@ -162,13 +162,13 @@ revert:
return -EAGAIN;
}
-static int pids_can_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static int pids_can_attach(struct cgroup_taskset *tset)
{
- struct pids_cgroup *pids = css_pids(css);
struct task_struct *task;
+ struct cgroup_subsys_state *dst_css;
- cgroup_taskset_for_each(task, tset) {
+ cgroup_taskset_for_each(task, dst_css, tset) {
+ struct pids_cgroup *pids = css_pids(dst_css);
struct cgroup_subsys_state *old_css;
struct pids_cgroup *old_pids;
@@ -187,13 +187,13 @@ static int pids_can_attach(struct cgroup_subsys_state *css,
return 0;
}
-static void pids_cancel_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static void pids_cancel_attach(struct cgroup_taskset *tset)
{
- struct pids_cgroup *pids = css_pids(css);
struct task_struct *task;
+ struct cgroup_subsys_state *dst_css;
- cgroup_taskset_for_each(task, tset) {
+ cgroup_taskset_for_each(task, dst_css, tset) {
+ struct pids_cgroup *pids = css_pids(dst_css);
struct cgroup_subsys_state *old_css;
struct pids_cgroup *old_pids;
@@ -205,65 +205,28 @@ static void pids_cancel_attach(struct cgroup_subsys_state *css,
}
}
+/*
+ * task_css_check(true) in pids_can_fork() and pids_cancel_fork() relies
+ * on threadgroup_change_begin() held by the copy_process().
+ */
static int pids_can_fork(struct task_struct *task, void **priv_p)
{
struct cgroup_subsys_state *css;
struct pids_cgroup *pids;
- int err;
- /*
- * Use the "current" task_css for the pids subsystem as the tentative
- * css. It is possible we will charge the wrong hierarchy, in which
- * case we will forcefully revert/reapply the charge on the right
- * hierarchy after it is committed to the task proper.
- */
- css = task_get_css(current, pids_cgrp_id);
+ css = task_css_check(current, pids_cgrp_id, true);
pids = css_pids(css);
-
- err = pids_try_charge(pids, 1);
- if (err)
- goto err_css_put;
-
- *priv_p = css;
- return 0;
-
-err_css_put:
- css_put(css);
- return err;
+ return pids_try_charge(pids, 1);
}
static void pids_cancel_fork(struct task_struct *task, void *priv)
{
- struct cgroup_subsys_state *css = priv;
- struct pids_cgroup *pids = css_pids(css);
-
- pids_uncharge(pids, 1);
- css_put(css);
-}
-
-static void pids_fork(struct task_struct *task, void *priv)
-{
struct cgroup_subsys_state *css;
- struct cgroup_subsys_state *old_css = priv;
struct pids_cgroup *pids;
- struct pids_cgroup *old_pids = css_pids(old_css);
- css = task_get_css(task, pids_cgrp_id);
+ css = task_css_check(current, pids_cgrp_id, true);
pids = css_pids(css);
-
- /*
- * If the association has changed, we have to revert and reapply the
- * charge/uncharge on the wrong hierarchy to the current one. Since
- * the association can only change due to an organisation event, its
- * okay for us to ignore the limit in this case.
- */
- if (pids != old_pids) {
- pids_uncharge(old_pids, 1);
- pids_charge(pids, 1);
- }
-
- css_put(css);
- css_put(old_css);
+ pids_uncharge(pids, 1);
}
static void pids_free(struct task_struct *task)
@@ -335,6 +298,7 @@ static struct cftype pids_files[] = {
{
.name = "current",
.read_s64 = pids_current_read,
+ .flags = CFTYPE_NOT_ON_ROOT,
},
{ } /* terminate */
};
@@ -346,7 +310,6 @@ struct cgroup_subsys pids_cgrp_subsys = {
.cancel_attach = pids_cancel_attach,
.can_fork = pids_can_fork,
.cancel_fork = pids_cancel_fork,
- .fork = pids_fork,
.free = pids_free,
.legacy_cftypes = pids_files,
.dfl_cftypes = pids_files,
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 10ae73611d80..02a8ea5c9963 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1429,15 +1429,16 @@ static int fmeter_getrate(struct fmeter *fmp)
static struct cpuset *cpuset_attach_old_cs;
/* Called by cgroups to determine if a cpuset is usable; cpuset_mutex held */
-static int cpuset_can_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static int cpuset_can_attach(struct cgroup_taskset *tset)
{
- struct cpuset *cs = css_cs(css);
+ struct cgroup_subsys_state *css;
+ struct cpuset *cs;
struct task_struct *task;
int ret;
/* used later by cpuset_attach() */
- cpuset_attach_old_cs = task_cs(cgroup_taskset_first(tset));
+ cpuset_attach_old_cs = task_cs(cgroup_taskset_first(tset, &css));
+ cs = css_cs(css);
mutex_lock(&cpuset_mutex);
@@ -1447,7 +1448,7 @@ static int cpuset_can_attach(struct cgroup_subsys_state *css,
(cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed)))
goto out_unlock;
- cgroup_taskset_for_each(task, tset) {
+ cgroup_taskset_for_each(task, css, tset) {
ret = task_can_attach(task, cs->cpus_allowed);
if (ret)
goto out_unlock;
@@ -1467,9 +1468,14 @@ out_unlock:
return ret;
}
-static void cpuset_cancel_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static void cpuset_cancel_attach(struct cgroup_taskset *tset)
{
+ struct cgroup_subsys_state *css;
+ struct cpuset *cs;
+
+ cgroup_taskset_first(tset, &css);
+ cs = css_cs(css);
+
mutex_lock(&cpuset_mutex);
css_cs(css)->attach_in_progress--;
mutex_unlock(&cpuset_mutex);
@@ -1482,16 +1488,19 @@ static void cpuset_cancel_attach(struct cgroup_subsys_state *css,
*/
static cpumask_var_t cpus_attach;
-static void cpuset_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static void cpuset_attach(struct cgroup_taskset *tset)
{
/* static buf protected by cpuset_mutex */
static nodemask_t cpuset_attach_nodemask_to;
struct task_struct *task;
struct task_struct *leader;
- struct cpuset *cs = css_cs(css);
+ struct cgroup_subsys_state *css;
+ struct cpuset *cs;
struct cpuset *oldcs = cpuset_attach_old_cs;
+ cgroup_taskset_first(tset, &css);
+ cs = css_cs(css);
+
mutex_lock(&cpuset_mutex);
/* prepare for attach */
@@ -1502,7 +1511,7 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
guarantee_online_mems(cs, &cpuset_attach_nodemask_to);
- cgroup_taskset_for_each(task, tset) {
+ cgroup_taskset_for_each(task, css, tset) {
/*
* can_attach beforehand should guarantee that this doesn't
* fail. TODO: have a better way to handle failure here
@@ -1518,7 +1527,7 @@ static void cpuset_attach(struct cgroup_subsys_state *css,
* sleep and should be moved outside migration path proper.
*/
cpuset_attach_nodemask_to = cs->effective_mems;
- cgroup_taskset_for_each_leader(leader, tset) {
+ cgroup_taskset_for_each_leader(leader, css, tset) {
struct mm_struct *mm = get_task_mm(leader);
if (mm) {
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index d659487254d5..9c418002b8c1 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -3,7 +3,7 @@
*
* Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
* Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar
- * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra
* Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
*
* For licensing details see kernel-base/COPYING
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 36babfd20648..ef2d6ea10736 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -3,7 +3,7 @@
*
* Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
* Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar
- * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra
* Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
*
* For licensing details see kernel-base/COPYING
@@ -435,7 +435,7 @@ static inline void update_cgrp_time_from_event(struct perf_event *event)
if (!is_cgroup_event(event))
return;
- cgrp = perf_cgroup_from_task(current);
+ cgrp = perf_cgroup_from_task(current, event->ctx);
/*
* Do not update time when cgroup is not active
*/
@@ -458,7 +458,7 @@ perf_cgroup_set_timestamp(struct task_struct *task,
if (!task || !ctx->nr_cgroups)
return;
- cgrp = perf_cgroup_from_task(task);
+ cgrp = perf_cgroup_from_task(task, ctx);
info = this_cpu_ptr(cgrp->info);
info->timestamp = ctx->timestamp;
}
@@ -489,7 +489,6 @@ static void perf_cgroup_switch(struct task_struct *task, int mode)
* we reschedule only in the presence of cgroup
* constrained events.
*/
- rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
@@ -522,8 +521,10 @@ static void perf_cgroup_switch(struct task_struct *task, int mode)
* set cgrp before ctxsw in to allow
* event_filter_match() to not have to pass
* task around
+ * we pass the cpuctx->ctx to perf_cgroup_from_task()
+ * because cgorup events are only per-cpu
*/
- cpuctx->cgrp = perf_cgroup_from_task(task);
+ cpuctx->cgrp = perf_cgroup_from_task(task, &cpuctx->ctx);
cpu_ctx_sched_in(cpuctx, EVENT_ALL, task);
}
perf_pmu_enable(cpuctx->ctx.pmu);
@@ -531,8 +532,6 @@ static void perf_cgroup_switch(struct task_struct *task, int mode)
}
}
- rcu_read_unlock();
-
local_irq_restore(flags);
}
@@ -542,17 +541,20 @@ static inline void perf_cgroup_sched_out(struct task_struct *task,
struct perf_cgroup *cgrp1;
struct perf_cgroup *cgrp2 = NULL;
+ rcu_read_lock();
/*
* we come here when we know perf_cgroup_events > 0
+ * we do not need to pass the ctx here because we know
+ * we are holding the rcu lock
*/
- cgrp1 = perf_cgroup_from_task(task);
+ cgrp1 = perf_cgroup_from_task(task, NULL);
/*
* next is NULL when called from perf_event_enable_on_exec()
* that will systematically cause a cgroup_switch()
*/
if (next)
- cgrp2 = perf_cgroup_from_task(next);
+ cgrp2 = perf_cgroup_from_task(next, NULL);
/*
* only schedule out current cgroup events if we know
@@ -561,6 +563,8 @@ static inline void perf_cgroup_sched_out(struct task_struct *task,
*/
if (cgrp1 != cgrp2)
perf_cgroup_switch(task, PERF_CGROUP_SWOUT);
+
+ rcu_read_unlock();
}
static inline void perf_cgroup_sched_in(struct task_struct *prev,
@@ -569,13 +573,16 @@ static inline void perf_cgroup_sched_in(struct task_struct *prev,
struct perf_cgroup *cgrp1;
struct perf_cgroup *cgrp2 = NULL;
+ rcu_read_lock();
/*
* we come here when we know perf_cgroup_events > 0
+ * we do not need to pass the ctx here because we know
+ * we are holding the rcu lock
*/
- cgrp1 = perf_cgroup_from_task(task);
+ cgrp1 = perf_cgroup_from_task(task, NULL);
/* prev can never be NULL */
- cgrp2 = perf_cgroup_from_task(prev);
+ cgrp2 = perf_cgroup_from_task(prev, NULL);
/*
* only need to schedule in cgroup events if we are changing
@@ -584,6 +591,8 @@ static inline void perf_cgroup_sched_in(struct task_struct *prev,
*/
if (cgrp1 != cgrp2)
perf_cgroup_switch(task, PERF_CGROUP_SWIN);
+
+ rcu_read_unlock();
}
static inline int perf_cgroup_connect(int fd, struct perf_event *event,
@@ -4216,7 +4225,14 @@ retry:
goto retry;
}
- __perf_event_period(&pe);
+ if (event->attr.freq) {
+ event->attr.sample_freq = value;
+ } else {
+ event->attr.sample_period = value;
+ event->hw.sample_period = value;
+ }
+
+ local64_set(&event->hw.period_left, 0);
raw_spin_unlock_irq(&ctx->lock);
return 0;
@@ -5667,6 +5683,17 @@ perf_event_aux_ctx(struct perf_event_context *ctx,
}
static void
+perf_event_aux_task_ctx(perf_event_aux_output_cb output, void *data,
+ struct perf_event_context *task_ctx)
+{
+ rcu_read_lock();
+ preempt_disable();
+ perf_event_aux_ctx(task_ctx, output, data);
+ preempt_enable();
+ rcu_read_unlock();
+}
+
+static void
perf_event_aux(perf_event_aux_output_cb output, void *data,
struct perf_event_context *task_ctx)
{
@@ -5675,14 +5702,23 @@ perf_event_aux(perf_event_aux_output_cb output, void *data,
struct pmu *pmu;
int ctxn;
+ /*
+ * If we have task_ctx != NULL we only notify
+ * the task context itself. The task_ctx is set
+ * only for EXIT events before releasing task
+ * context.
+ */
+ if (task_ctx) {
+ perf_event_aux_task_ctx(output, data, task_ctx);
+ return;
+ }
+
rcu_read_lock();
list_for_each_entry_rcu(pmu, &pmus, entry) {
cpuctx = get_cpu_ptr(pmu->pmu_cpu_context);
if (cpuctx->unique_pmu != pmu)
goto next;
perf_event_aux_ctx(&cpuctx->ctx, output, data);
- if (task_ctx)
- goto next;
ctxn = pmu->task_ctx_nr;
if (ctxn < 0)
goto next;
@@ -5692,12 +5728,6 @@ perf_event_aux(perf_event_aux_output_cb output, void *data,
next:
put_cpu_ptr(pmu->pmu_cpu_context);
}
-
- if (task_ctx) {
- preempt_disable();
- perf_event_aux_ctx(task_ctx, output, data);
- preempt_enable();
- }
rcu_read_unlock();
}
@@ -8787,10 +8817,8 @@ static void perf_event_exit_task_context(struct task_struct *child, int ctxn)
struct perf_event_context *child_ctx, *clone_ctx = NULL;
unsigned long flags;
- if (likely(!child->perf_event_ctxp[ctxn])) {
- perf_event_task(child, NULL, 0);
+ if (likely(!child->perf_event_ctxp[ctxn]))
return;
- }
local_irq_save(flags);
/*
@@ -8874,6 +8902,14 @@ void perf_event_exit_task(struct task_struct *child)
for_each_task_context_nr(ctxn)
perf_event_exit_task_context(child, ctxn);
+
+ /*
+ * The perf_event_exit_task_context calls perf_event_task
+ * with child's task_ctx, which generates EXIT events for
+ * child contexts and sets child->perf_event_ctxp[] to NULL.
+ * At this point we need to send EXIT events to cpu contexts.
+ */
+ perf_event_task(child, NULL, 0);
}
static void perf_free_event(struct perf_event *event,
@@ -9452,16 +9488,18 @@ static void perf_cgroup_css_free(struct cgroup_subsys_state *css)
static int __perf_cgroup_move(void *info)
{
struct task_struct *task = info;
+ rcu_read_lock();
perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN);
+ rcu_read_unlock();
return 0;
}
-static void perf_cgroup_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static void perf_cgroup_attach(struct cgroup_taskset *tset)
{
struct task_struct *task;
+ struct cgroup_subsys_state *css;
- cgroup_taskset_for_each(task, tset)
+ cgroup_taskset_for_each(task, css, tset)
task_function_call(task, __perf_cgroup_move, task);
}
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index b5d1ea79c595..adfdc0536117 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -3,7 +3,7 @@
*
* Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
* Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar
- * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra
* Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
*
* For licensing details see kernel-base/COPYING
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 4e5e9798aa0c..7dad84913abf 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -19,7 +19,7 @@
* Authors:
* Srikar Dronamraju
* Jim Keniston
- * Copyright (C) 2011-2012 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2011-2012 Red Hat, Inc., Peter Zijlstra
*/
#include <linux/kernel.h>
diff --git a/kernel/fork.c b/kernel/fork.c
index f97f2c449f5c..fce002ee3ddf 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1368,8 +1368,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->real_start_time = ktime_get_boot_ns();
p->io_context = NULL;
p->audit_context = NULL;
- if (clone_flags & CLONE_THREAD)
- threadgroup_change_begin(current);
+ threadgroup_change_begin(current);
cgroup_fork(p);
#ifdef CONFIG_NUMA
p->mempolicy = mpol_dup(p->mempolicy);
@@ -1610,8 +1609,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
proc_fork_connector(p);
cgroup_post_fork(p, cgrp_ss_priv);
- if (clone_flags & CLONE_THREAD)
- threadgroup_change_end(current);
+ threadgroup_change_end(current);
perf_event_fork(p);
trace_task_newtask(p, clone_flags);
@@ -1652,8 +1650,7 @@ bad_fork_cleanup_policy:
mpol_put(p->mempolicy);
bad_fork_cleanup_threadgroup_lock:
#endif
- if (clone_flags & CLONE_THREAD)
- threadgroup_change_end(current);
+ threadgroup_change_end(current);
delayacct_tsk_free(p);
bad_fork_cleanup_count:
atomic_dec(&p->cred->user->processes);
diff --git a/kernel/irq_work.c b/kernel/irq_work.c
index cbf9fb899d92..bcf107ce0854 100644
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2010 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2010 Red Hat, Inc., Peter Zijlstra
*
* Provides a framework for enqueueing and running callbacks from hardirq
* context. The enqueueing is NMI-safe.
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index f7dd15d537f9..05254eeb4b4e 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -2,7 +2,7 @@
* jump label support
*
* Copyright (C) 2009 Jason Baron <jbaron@redhat.com>
- * Copyright (C) 2011 Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2011 Peter Zijlstra
*
*/
#include <linux/memory.h>
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index deae3907ac1e..60ace56618f6 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -6,7 +6,7 @@
* Started by Ingo Molnar:
*
* Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
*
* this code maps all the lock dependencies as they occur in a live kernel
* and will warn about the following classes of locking bugs:
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index d83d798bef95..dbb61a302548 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -6,7 +6,7 @@
* Started by Ingo Molnar:
*
* Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
*
* Code for /proc/lockdep and /proc/lockdep_stats:
*
diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c
index d092a0c9c2d4..05a37857ab55 100644
--- a/kernel/locking/osq_lock.c
+++ b/kernel/locking/osq_lock.c
@@ -93,10 +93,12 @@ bool osq_lock(struct optimistic_spin_queue *lock)
node->cpu = curr;
/*
- * ACQUIRE semantics, pairs with corresponding RELEASE
- * in unlock() uncontended, or fastpath.
+ * We need both ACQUIRE (pairs with corresponding RELEASE in
+ * unlock() uncontended, or fastpath) and RELEASE (to publish
+ * the node fields we just initialised) semantics when updating
+ * the lock tail.
*/
- old = atomic_xchg_acquire(&lock->tail, curr);
+ old = atomic_xchg(&lock->tail, curr);
if (old == OSQ_UNLOCKED_VAL)
return true;
diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index c0a205101c23..caf4041f5b0a 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -1,7 +1,7 @@
/*
* sched_clock for unstable cpu clocks
*
- * Copyright (C) 2008 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2008 Red Hat, Inc., Peter Zijlstra
*
* Updates and enhancements:
* Copyright (C) 2008 Red Hat, Inc. Steven Rostedt <srostedt@redhat.com>
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 4d568ac9319e..732e993b564b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1947,13 +1947,38 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
#ifdef CONFIG_SMP
/*
+ * Ensure we load p->on_cpu _after_ p->on_rq, otherwise it would be
+ * possible to, falsely, observe p->on_cpu == 0.
+ *
+ * One must be running (->on_cpu == 1) in order to remove oneself
+ * from the runqueue.
+ *
+ * [S] ->on_cpu = 1; [L] ->on_rq
+ * UNLOCK rq->lock
+ * RMB
+ * LOCK rq->lock
+ * [S] ->on_rq = 0; [L] ->on_cpu
+ *
+ * Pairs with the full barrier implied in the UNLOCK+LOCK on rq->lock
+ * from the consecutive calls to schedule(); the first switching to our
+ * task, the second putting it to sleep.
+ */
+ smp_rmb();
+
+ /*
* If the owning (remote) cpu is still in the middle of schedule() with
* this task as prev, wait until its done referencing the task.
*/
while (p->on_cpu)
cpu_relax();
/*
- * Pairs with the smp_wmb() in finish_lock_switch().
+ * Combined with the control dependency above, we have an effective
+ * smp_load_acquire() without the need for full barriers.
+ *
+ * Pairs with the smp_store_release() in finish_lock_switch().
+ *
+ * This ensures that tasks getting woken will be fully ordered against
+ * their previous state and preserve Program Order.
*/
smp_rmb();
@@ -2039,7 +2064,6 @@ out:
*/
int wake_up_process(struct task_struct *p)
{
- WARN_ON(task_is_stopped_or_traced(p));
return try_to_wake_up(p, TASK_NORMAL, 0);
}
EXPORT_SYMBOL(wake_up_process);
@@ -5847,13 +5871,13 @@ static int init_rootdomain(struct root_domain *rd)
{
memset(rd, 0, sizeof(*rd));
- if (!alloc_cpumask_var(&rd->span, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL))
goto out;
- if (!alloc_cpumask_var(&rd->online, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&rd->online, GFP_KERNEL))
goto free_span;
- if (!alloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL))
goto free_online;
- if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
+ if (!zalloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
goto free_dlo_mask;
init_dl_bw(&rd->dl_bw);
@@ -8217,12 +8241,12 @@ static void cpu_cgroup_fork(struct task_struct *task, void *private)
sched_move_task(task);
}
-static int cpu_cgroup_can_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static int cpu_cgroup_can_attach(struct cgroup_taskset *tset)
{
struct task_struct *task;
+ struct cgroup_subsys_state *css;
- cgroup_taskset_for_each(task, tset) {
+ cgroup_taskset_for_each(task, css, tset) {
#ifdef CONFIG_RT_GROUP_SCHED
if (!sched_rt_can_attach(css_tg(css), task))
return -EINVAL;
@@ -8235,12 +8259,12 @@ static int cpu_cgroup_can_attach(struct cgroup_subsys_state *css,
return 0;
}
-static void cpu_cgroup_attach(struct cgroup_subsys_state *css,
- struct cgroup_taskset *tset)
+static void cpu_cgroup_attach(struct cgroup_taskset *tset)
{
struct task_struct *task;
+ struct cgroup_subsys_state *css;
- cgroup_taskset_for_each(task, tset)
+ cgroup_taskset_for_each(task, css, tset)
sched_move_task(task);
}
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 26a54461bf59..05de80b48586 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -788,6 +788,9 @@ cputime_t task_gtime(struct task_struct *t)
unsigned int seq;
cputime_t gtime;
+ if (!context_tracking_is_enabled())
+ return t->gtime;
+
do {
seq = read_seqbegin(&t->vtime_seqlock);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index f04fda8f669c..90e26b11deaa 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -17,7 +17,7 @@
* Copyright (C) 2007, Thomas Gleixner <tglx@linutronix.de>
*
* Adaptive scheduling granularity, math enhancements by Peter Zijlstra
- * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
*/
#include <linux/latencytop.h>
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index e3cc16312046..8ec86abe0ea1 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -64,7 +64,7 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
raw_spin_unlock(&rt_b->rt_runtime_lock);
}
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) && defined(HAVE_RT_PUSH_IPI)
static void push_irq_work_func(struct irq_work *work);
#endif
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index efd3bfc7e347..b242775bf670 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1073,6 +1073,9 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
* We must ensure this doesn't happen until the switch is completely
* finished.
*
+ * In particular, the load of prev->state in finish_task_switch() must
+ * happen before this.
+ *
* Pairs with the control dependency and rmb in try_to_wake_up().
*/
smp_store_release(&prev->on_cpu, 0);
diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c
index 052e02672d12..f15d6b6a538a 100644
--- a/kernel/sched/wait.c
+++ b/kernel/sched/wait.c
@@ -392,7 +392,7 @@ __wait_on_bit(wait_queue_head_t *wq, struct wait_bit_queue *q,
do {
prepare_to_wait(wq, &q->wait, mode);
if (test_bit(q->key.bit_nr, q->key.flags))
- ret = (*action)(&q->key);
+ ret = (*action)(&q->key, mode);
} while (test_bit(q->key.bit_nr, q->key.flags) && !ret);
finish_wait(wq, &q->wait);
return ret;
@@ -431,7 +431,7 @@ __wait_on_bit_lock(wait_queue_head_t *wq, struct wait_bit_queue *q,
prepare_to_wait_exclusive(wq, &q->wait, mode);
if (!test_bit(q->key.bit_nr, q->key.flags))
continue;
- ret = action(&q->key);
+ ret = action(&q->key, mode);
if (!ret)
continue;
abort_exclusive_wait(wq, &q->wait, mode, &q->key);
@@ -581,44 +581,44 @@ void wake_up_atomic_t(atomic_t *p)
}
EXPORT_SYMBOL(wake_up_atomic_t);
-__sched int bit_wait(struct wait_bit_key *word)
+__sched int bit_wait(struct wait_bit_key *word, int mode)
{
- if (signal_pending_state(current->state, current))
- return 1;
schedule();
+ if (signal_pending_state(mode, current))
+ return -EINTR;
return 0;
}
EXPORT_SYMBOL(bit_wait);
-__sched int bit_wait_io(struct wait_bit_key *word)
+__sched int bit_wait_io(struct wait_bit_key *word, int mode)
{
- if (signal_pending_state(current->state, current))
- return 1;
io_schedule();
+ if (signal_pending_state(mode, current))
+ return -EINTR;
return 0;
}
EXPORT_SYMBOL(bit_wait_io);
-__sched int bit_wait_timeout(struct wait_bit_key *word)
+__sched int bit_wait_timeout(struct wait_bit_key *word, int mode)
{
unsigned long now = READ_ONCE(jiffies);
- if (signal_pending_state(current->state, current))
- return 1;
if (time_after_eq(now, word->timeout))
return -EAGAIN;
schedule_timeout(word->timeout - now);
+ if (signal_pending_state(mode, current))
+ return -EINTR;
return 0;
}
EXPORT_SYMBOL_GPL(bit_wait_timeout);
-__sched int bit_wait_io_timeout(struct wait_bit_key *word)
+__sched int bit_wait_io_timeout(struct wait_bit_key *word, int mode)
{
unsigned long now = READ_ONCE(jiffies);
- if (signal_pending_state(current->state, current))
- return 1;
if (time_after_eq(now, word->timeout))
return -EAGAIN;
io_schedule_timeout(word->timeout - now);
+ if (signal_pending_state(mode, current))
+ return -EINTR;
return 0;
}
EXPORT_SYMBOL_GPL(bit_wait_io_timeout);
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 867bc20e1ef1..a3bbaee77c58 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -531,7 +531,7 @@ static int __init cpu_stop_init(void)
}
early_initcall(cpu_stop_init);
-#ifdef CONFIG_STOP_MACHINE
+#if defined(CONFIG_SMP) || defined(CONFIG_HOTPLUG_CPU)
static int __stop_machine(cpu_stop_fn_t fn, void *data, const struct cpumask *cpus)
{
@@ -631,4 +631,4 @@ int stop_machine_from_inactive_cpu(cpu_stop_fn_t fn, void *data,
return ret ?: done.ret;
}
-#endif /* CONFIG_STOP_MACHINE */
+#endif /* CONFIG_SMP || CONFIG_HOTPLUG_CPU */
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index abfc903e741e..cc9f7a9319be 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -1,7 +1,7 @@
/*
* trace event based perf event profiling/tracing
*
- * Copyright (C) 2009 Red Hat Inc, Peter Zijlstra <pzijlstr@redhat.com>
+ * Copyright (C) 2009 Red Hat Inc, Peter Zijlstra
* Copyright (C) 2009-2010 Frederic Weisbecker <fweisbec@gmail.com>
*/